Seed Germination as an Adaptive Response in Halophytes

Halophytes thrive in saline habitats through highly specialized adaptive responses, including seed-based strategies to regulate germination timing and ensure reproductive success under fluctuating environmental conditions. Salt-induced quiescence, structural alteration, and regulatory mechanisms are valuable adaptive strategies that facilitate plant growth under high saline conditions, which are becoming increasingly severe due to global climate change. This review provides an overview of the current understanding of halophyte seed germination, dormancy, and recovery. Low to moderate salt exposure generally causes reversible inhibition of germination; however, prolonged or high-level exposure causes stress-induced seed damage. On the other hand, halophyte seeds exhibit regulatory mechanisms associated with germination inhibition under high salt conditions. Adaptive traits such as seed heteromorphism, protective seed coats, mucilage production, and physiological dormancy enhance survival and establishment in saline soils. The ability of halophyte seeds to maintain viability under high salinity and to germinate rapidly when salt stress is alleviated indicates the preservation of metabolic and cellular integrity. Structural adaptations, regulatory mechanisms that balance germination, and the salt-induced quiescent process are controlled by morphological changes and molecular mechanisms. Furthermore, this review highlights the ecological significance and potential applications of halophyte seeds for crop improvement and the restoration of saline and degraded lands. Therefore, understanding the regulatory mechanisms of halophyte seed behavior is a valuable approach for enhancing plant resilience to salinity stress.